This is a functional and morphological study of retinal growth and its consequences in a teleost fish, the goldfish. These animals' retinas grow by adding new cells to an already functional retina. There are four areas of investigation: 1) a light and electron microscopic examination of the growing retina and optic nerve, 2) an electrophysiological examination of growing retina and optic nerve, 3) a light and electron microscopic examination of growth-related changes in the optic tectum and lateral geniculate nucleus, and 4) a light and electron microscopic examination of the growth-related changes in the ocular motor system.